staging: rtl8188eu: core: rtw_mlme: Remove return statement from void function

Remove the return statement from the end of a void function
to clean up the code.

Issue found by checkpatch.pl script.

Signed-off-by: Georgiana Rodica Chelu <georgiana.chelu93@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>